The present disclosure relates to a semiconductor structure, and particularly to a semiconductor structure including electrically isolated SiGe fins, and a method for manufacturing the same.
A finFET is field effect transistor including a channel located in a semiconductor fin having a height that is greater than a width. FinFETs employ vertical surfaces of semiconductor fins to effectively increase a device area without increasing the physical layout area of the device. Fin based devices are compatible with fully depleted mode operation if the lateral width of the fin is thin enough. For these reasons, fin based devices can be employed in advanced semiconductor chips to provide high performance devices.
Formation of a silicon germanium alloy fin including a high concentration of germanium on a silicon substrate is difficult because of large lattice mismatch between silicon and germanium. As the atomic germanium concentration increases in a silicon germanium alloy that is epitaxially formed on a silicon layer, defect density within the silicon germanium alloy also increases. Silicon germanium alloy fins patterned from the silicon germanium alloy also include high density of defects, which degrade performance of semiconductor devices formed on the silicon germanium alloy fins.